Coypu

Fascinating facts about the Coypu

• A coypu can hold its breath for 5 minutes underwater, but it doesn't need to — its eyes, ears, and nostrils sit on top of its head like a crocodile's, letting it hunt submerged plants while staying almost completely hidden. This design lets a single coypu eat up to 3.5 kg of vegetation daily, enough to transform a wetland from lush to barren in months.
• Female coypus are pregnant for just 128 days, then give birth to fully furred, open-eyed pups that can swim and forage within hours. A mother can breed year-round in warm climates, producing up to 3 litters annually — a reproductive strategy so aggressive that coypus have become one of the world's most successful invasive mammals across Europe, Africa, and Asia.
• Unlike most rodents, a coypu's teeth never stop growing, but they stay sharp and functional because they're coated in enamel only on the front surface; the softer dentin behind wears away naturally, creating a self-sharpening blade. This is why they can gnaw through wooden wetland structures and dig burrows that destabilise riverbanks across entire regions.
• A coypu weighs 7–10 kg and looks like a giant rat, but it's actually closer related to chinchillas and guinea pigs than to rats — a quirk of rodent evolution that left it with a body plan perfectly suited for semi-aquatic life that rats never evolved. Its hind feet are partly webbed and its tail is round, not flat, making it a poor swimmer compared to beavers but efficient enough to colonise new wetlands faster than any native competitor.
• In 1960s Britain, the government launched a £250,000 campaign to eradicate coypus after they'd spread from fur farms across East Anglia, destroying wetland habitats that had existed for centuries. By 1989, they'd killed the last wild coypu in the UK through a combination of trapping, poisoning, and habitat destruction — one of the few successful eradications of an invasive mammal at national scale, a warning that early action works and delay costs millions.

At a glance

About the Coypu

In the lush, verdant wetlands, a semi-aquatic giant stirs, its webbed hind feet paddling softly as it glides across the water's surface with an air of serene elegance. The coypu, with its coarse, reddish-brown fur and bright orange teeth, is a master of its domain, navigating the dense vegetation with a quiet confidence that belies its remarkable adaptability. As it moves, the water ripples and the surrounding plants sway, a testament to the coypu's gentle yet unyielding presence in this delicate ecosystem.

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